Please do not hold the string by your hand when wrapping or stretching it as this may cause burns.Also, be careful not to hit the string when using.If you are using it on a road, sidewalk or other way, please shorten the cord and tighten it to allow your dog to control.To prevent accidents, please do not use for dogs other than the appropriate size and weight of the product.However, please be aware of the dogs habit, and if you are pulling it hard, please buy a product that has enough room for the proper weight.This product is a consumable product, so please be sure to inspect before use and replace it with a new one.It is an estimation of about 6 months.Please check the straps, snaps, and lock parts carefully.